 |
| Titel |
Contact discontinuities in solar wind |
| VerfasserIn |
Wen-Chieh Hsieh, Jih-Hong Shue, Jih-Kwin Chao, Tsung-Che Tsai, Zdenek Nemecek, Jana Safrankova, Oksana Kruparova |
| Konferenz |
EGU General Assembly 2014
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 16 (2014) |
| Datensatznummer |
250096222
|
| Publikation (Nr.) |
 EGU/EGU2014-11716.pdf |
|
|
|
|
|
| Zusammenfassung |
| Contact discontinuities (CD) are discontinuities that have magnetic fields linked between two
sides but no plasma flows across its surface. Due to the lack of demonstrations of CD in
observation, their stable existence is still under debate. Contact discontinuities are not
expected to be observed in the solar wind because of the rapid diffusion of plasma along the
magnetic fields across their surfaces. Nevertheless, hybrid simulations had demonstrated that
stable CD can exist with a finite ratio of the electron temperature to ion temperature; but
full particle simulations predicted that CD cannot persist in collisionless plasma
as a result of electron thermal transport. On the other hand, electrostatic Vlasov
simulations show that the structure of a contact discontinuity can be stable under a
condition of out-of-phase profiles of the ion and electron temperatures. According to
theoretical considerations, CD can survive in magnetodynamics plasma with constant
total thermal pressure across the surface of CD, in ion-electron two-fluid plasma
further with out-of-phase variations of the ion and electron thermal pressures, and in
Vlasov theory with additionally out-of-phase variations of the ion and electron
temperatures. In this study, we define the criteria for the selection of a CD event
in observation, in accord with the jump conditions. CD events in the solar wind,
with a constant total thermal pressure but different performances on the variations
of thermal pressure and temperatures of ions and electrons will be demonstrated.
The practical behavior of ion and electron temperature will be discussed in follow. |
|
|
|
|
|
|